<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0"
	xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns="http://www.w3.org/1999/xhtml">

	<xsl:output method="xml" />
	<xsl:variable name='ciudad' select="'cadiz'" />

	<xsl:template match="/">
		<graphml>
			<graph>
			<xsl:for-each select="//edge[@source = $ciudad]">
				<xsl:copy-of select="." />
			</xsl:for-each>
			</graph>
		</graphml>		
	</xsl:template>

</xsl:stylesheet>
